Vera Czehmann
2026
"A Sacred Bird Called the Phoenix". Auditing the most-used Parallel Corpus for German Sign Language Recognition and Translation
Vera Czehmann | Shakib Yazdani | Yasser Hamidullah | Fabrizio Nunnari | Eleftherios Avramidis
Proceedings of the LREC 2026 12th Workshop on the Representation and Processing of Sign Languages: Language in Motion
Vera Czehmann | Shakib Yazdani | Yasser Hamidullah | Fabrizio Nunnari | Eleftherios Avramidis
Proceedings of the LREC 2026 12th Workshop on the Representation and Processing of Sign Languages: Language in Motion
This paper presents an empirical audit of the widely used RWTH-PHOENIX-2014T corpus, examining its suitability as a benchmark for sign language recognition and translation. Through human annotation of the training set and extensive sign-to-text back translation of the test set, we provide detailed statistics that indicate substantial quality issues, including information loss and lexical errors. Automatic scores comparing human sign-to-text back translations to the original speech transcribed references are remarkably low, suggesting strong translationese effects and substantial paraphrasing, revealing limitations of lexical metrics in adequately scoring translation quality. Replacing the original speech-transcribed references with human sign-to-text back translations while scoring existing sign language translation systems reveals the lack of robustness of system evaluation with lexical metrics against this test set. Our findings highlight risks associated with relying on this corpus for model evaluation and call for more rigorous, linguistically grounded evaluation practices in sign language technology research. The back-translated test set and error annotations are made publicly available.
Developing Annotation Guidelines for CSAM Prevention Interventions: Psychosocial Risk and Protective Factors Grounded in Research and Clinical Practice
Vera Czehmann | Christine Hovhannisyan | Lena Elisabeth Hoffmann | Paula Busch | Ibrahim Baroud | Sebastian Möller | Roland Roller | Hannes Gieseler | Lisa Raithel
Proceedings of the Sixth Resources and ProcessIng of linguistic, para-linguistic and extra-linguistic Data from people with various forms of cognitive/psychiatric/developmental impairments in cooperation with the MENTAL.ai consortium
Vera Czehmann | Christine Hovhannisyan | Lena Elisabeth Hoffmann | Paula Busch | Ibrahim Baroud | Sebastian Möller | Roland Roller | Hannes Gieseler | Lisa Raithel
Proceedings of the Sixth Resources and ProcessIng of linguistic, para-linguistic and extra-linguistic Data from people with various forms of cognitive/psychiatric/developmental impairments in cooperation with the MENTAL.ai consortium
This work discusses sexual offending, specifically child sexual abuse material (CSAM), in the context of prevention. We introduce a domain-specific, span-level annotation scheme and guidelines to identify psychosocial risk and protective factors in therapist-led, anonymous chat interventions with voluntarily help-seeking individuals concerned about their pedophilic interests and the risk of CSAM use. The scheme is grounded in previous research and clinical experience, and intended for within-intervention guidance and longitudinal tracking, rather than actuarial risk scoring. Annotating a pilot subset (8 clients, 31 sessions), inter-annotator agreement was moderate but improved after calibration, which is consistent with the linguistic and clinical ambivalence present in the data. We track a session-wise Protective Ratio, i.e., the share of protective factors among all coded factors, and examine its behaviour over time during the intervention and around self-reported relapse within clients. In exploratory automation, LLM-based span extraction outperforms BERT baselines but overall performance remains limited by small data and mixed-evidence spans. While complete anonymisation of the corpus is in progress, we release the label scheme, guidelines, and non-sensitive artefacts of our analyses.
MultiGraSCCo: A Multilingual Anonymization Benchmark with Annotations of Personal Identifiers
Ibrahim Baroud | Christoph Otto | Vera Czehmann | Christine Hovhannisyan | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Ibrahim Baroud | Christoph Otto | Vera Czehmann | Christine Hovhannisyan | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Accessing sensitive patient data for machine learning is challenging due to privacy concerns. Datasets with annotations of personally identifiable information are crucial for developing and testing anonymization systems, which would enable safe data sharing that complies with privacy regulations. Since accessing real patient data is a bottleneck, synthetic data offers an efficient solution for data scarcity, bypassing privacy regulations that apply to real data. Moreover, neural machine translation can help to create high-quality data for low-resource languages by translating validated real or synthetic data from a high-resource language. In this work, we create a multilingual anonymization benchmark in ten languages, using a machine translation methodology that preserves the original annotations and renders city and people names in a culturally and contextually appropriate form in each target language. Our evaluation study with medical professionals confirms the quality of the translations, both in general and with respect to the translation and adaptation of personal information. Our benchmark with over 2,500 annotations of personal information can be used in many applications, including training annotators, validating annotations across institutions without legal complications, and helping improve the performance of automatic personal information detection. We make our benchmark and annotation guidelines available for further research.
2023
Neural Machine Translation Methods for Translating Text to Sign Language Glosses
Dele Zhu | Vera Czehmann | Eleftherios Avramidis
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Dele Zhu | Vera Czehmann | Eleftherios Avramidis
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
State-of-the-art techniques common to low resource Machine Translation (MT) are applied to improve MT of spoken language text to Sign Language (SL) glosses. In our experiments, we improve the performance of the transformer-based models via (1) data augmentation, (2) semi-supervised Neural Machine Translation (NMT), (3) transfer learning and (4) multilingual NMT. The proposed methods are implemented progressively on two German SL corpora containing gloss annotations. Multilingual NMT combined with data augmentation appear to be the most successful setting, yielding statistically significant improvements as measured by three automatic metrics (up to over 6 points BLEU), and confirmed via human evaluation. Our best setting outperforms all previous work that report on the same test-set and is also confirmed on a corpus of the American Sign Language (ASL).